test(sdk): cover browser DOM integrations

packages/sdk/package.json

@@ -73,6 +73,7 @@
     "@types/express": "^5.0.6",
     "@types/react": "^18.3.3",
     "@types/supertest": "^7.2.1",
+    "jsdom": "^30.1.1",
     "openapi-typescript": "^7.13.0",
     "supertest": "^7.2.2",
     "tsup": "^8.0.0",

packages/sdk/src/client.stream.dom.test.ts

@@ -0,0 +1,45 @@
+/** @vitest-environment jsdom */
+import { afterEach, describe, expect, it, vi } from 'vitest';
+import { AccensaClient } from './client';
+import type { SyncEvent } from './types/sync-event';
+
+class MockEventSource extends EventTarget {
+  static instances: MockEventSource[] = [];
+  readonly close = vi.fn();
+
+  constructor(readonly url: string) {
+    super();
+    MockEventSource.instances.push(this);
+  }
+}
+
+describe('AccensaClient sync event stream', () => {
+  afterEach(() => {
+    vi.unstubAllGlobals();
+    MockEventSource.instances = [];
+  });
+
+  it('delivers sync events and closes the stream when unsubscribed', () => {
+    vi.stubGlobal('EventSource', MockEventSource);
+    const client = new AccensaClient({ indexerUrl: 'https://indexer.example' });
+    const onSync = vi.fn();
+    const unsubscribe = client.subscribeSync({ onSync });
+    const source = MockEventSource.instances[0];
+    const payload: SyncEvent = {
+      merchant: 'G' + 'A'.repeat(55),
+      syncedTo: 42,
+      inserted: 2,
+      scanned: 3,
+      pages: 1,
+      drained: true,
+      occurredAt: '2026-10-17T00:00:00.000Z',
+    };
+
+    source.dispatchEvent(new MessageEvent('sync', { data: JSON.stringify(payload) }));
+
+    expect(source.url).toBe('https://indexer.example/api/sync/stream');
+    expect(onSync).toHaveBeenCalledWith(payload);
+    unsubscribe();
+    expect(source.close).toHaveBeenCalledOnce();
+  });
+});

packages/sdk/src/offline-sync.dom.test.ts

@@ -0,0 +1,28 @@
+/** @vitest-environment jsdom */
+import { afterEach, describe, expect, it } from 'vitest';
+import { OfflineSyncEngine } from './offline-sync';
+
+describe('OfflineSyncEngine in a browser DOM', () => {
+  afterEach(() => {
+    localStorage.clear();
+    window.dispatchEvent(new Event('online'));
+  });
+
+  it('persists queued work offline and flushes it when connectivity returns', async () => {
+    Object.defineProperty(navigator, 'onLine', { configurable: true, value: true });
+    const engine = new OfflineSyncEngine({ storageKey: 'offline-dom-test', syncIntervalMs: 0 });
+    await engine.init();
+
+    window.dispatchEvent(new Event('offline'));
+    engine.queueUpdate('orders', 'order-1', { status: 'ready' });
+
+    expect(engine.getPendingCount()).toBe(1);
+    expect(JSON.parse(localStorage.getItem('offline-dom-test')!).pendingOps).toHaveLength(1);
+
+    window.dispatchEvent(new Event('online'));
+    await Promise.resolve();
+
+    expect(engine.getPendingCount()).toBe(0);
+    expect(JSON.parse(localStorage.getItem('offline-dom-test')!).pendingOps).toHaveLength(0);
+  });
+});

packages/sdk/src/widget/checkout-widget.dom.test.ts

@@ -0,0 +1,28 @@
+/** @vitest-environment jsdom */
+import { afterEach, describe, expect, it, vi } from 'vitest';
+import { AccensaCheckoutWidget } from './checkout-widget';
+
+describe('AccensaCheckoutWidget DOM lifecycle', () => {
+  afterEach(() => {
+    vi.restoreAllMocks();
+    document.body.replaceChildren();
+  });
+
+  it('renders when connected and removes its message listener on disconnect', () => {
+    expect(customElements.get('accensa-checkout')).toBe(AccensaCheckoutWidget);
+    const add = vi.spyOn(window, 'addEventListener');
+    const remove = vi.spyOn(window, 'removeEventListener');
+    const widget = document.createElement('accensa-checkout') as AccensaCheckoutWidget;
+    widget.setAttribute('amount', '12.50');
+    document.body.append(widget);
+
+    expect(widget.shadowRoot?.textContent).toContain('12.50');
+    const registered = add.mock.calls.find(([type]) => type === 'message')?.[1];
+    expect(registered).toBeTypeOf('function');
+
+    widget.remove();
+
+    const removed = remove.mock.calls.find(([type]) => type === 'message')?.[1];
+    expect(removed).toBe(registered);
+  });
+});

packages/sdk/src/widget/checkout-widget.ts

@@ -67,7 +67,7 @@ class AccensaCheckoutWidget extends HTMLElementBase {
   }
 
   disconnectedCallback() {
-    window.removeEventListener('message', this.handleMessage);
+    window.removeEventListener('message', this.boundHandleMessage);
   }
 
   attributeChangedCallback(name: string, oldValue: string, newValue: string) {
@@ -88,7 +88,7 @@ class AccensaCheckoutWidget extends HTMLElementBase {
   }
 
   private setupMessageListener() {
-    window.addEventListener('message', this.handleMessage.bind(this));
+    window.addEventListener('message', this.boundHandleMessage);
   }
 
   private handleMessage = (event: MessageEvent<ParentMessage>) => {
@@ -119,6 +119,9 @@ class AccensaCheckoutWidget extends HTMLElementBase {
     }
   };
 
+  // Retain the same bound callback so disconnection can remove the listener.
+  private boundHandleMessage = this.handleMessage.bind(this);
+
   private postMessage(message: WidgetMessage, targetOrigin: string = MESSAGE_ORIGIN) {
     if (this.messageId > 10000) {
       this.messageId = 0; // Prevent overflow

packages/sdk/vitest.config.ts

@@ -2,6 +2,8 @@ import { defineConfig } from 'vitest/config';
 
 export default defineConfig({
   test: {
+    // DOM tests opt in with a per-file @vitest-environment jsdom docblock so
+    // the SDK's existing Node-only tests keep their current runtime.
     /**
      * `tsc` now runs alongside the suite, which starves the event loop enough
      * on a loaded machine to push the timer-driven tests (the abort and retry